1. Field of the Invention
The present invention relates to hopper cars of the type which discharges material through side discharge openings normally closed by means of outwardly swinging doors. More particularly the invention relates to a trackside closure mechanism positioned to close the swinging doors on both sides of the railway hopper car, irrespective of any parallelograming of the car, as it passes along the track into association with the closing mechanism.
2. Description of the Prior Art
Some of the patents exemplifying the prior art are U.S. Pat. Nos. 4,120,412; 3,897,877; 3,169,648; 3,151,751; 2,529,588; 2,086,283 and 1,414,760. In U.S. Pat. No. 4,120,412 the device operates in a relatively normal upright position and compensates for normal side sway or rolling movements of the car. However, beyond its limited capabilities it cannot reach out and fully close the door on the side of the car tilted away from the device beyond its operating parameters. In U.S. Pat. Nos. 3,897,877; 3,169,648; 3,151,751; 2,529,588 and 2,086,283 show various method of orientating, aligning and squeezing boxes, freight and the like and do not show or suggest the arrangement herein contemplated. U.S. Pat. No. 1,414,760 shows a device whereby the door of a mine car may be automatically opened but does not suggest compensating or conjoint movement.